Plated sealing system for vehicle assembly

ABSTRACT

A sealing system includes an exterior plate, an interior plate, a first seal received against the exterior plate and configured to restrict moisture ingress through the exterior plate, and a second seal received against the interior plate and configured to restrict moisture ingress through the interior plate. The sealing system may be used to seal around tubing that extends through a vehicle battery enclosure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a divisional of U.S. patent application Ser. No. 14/640,358,which was filed on Mar. 6, 2015.

TECHNICAL FIELD

This disclosure relates to a vehicle assembly for an electrifiedvehicle. The vehicle assembly includes a sealing system configured torestrict moisture ingress through a wall of the assembly.

BACKGROUND

The need to reduce automotive fuel consumption and emissions is wellknown. Therefore, vehicles are being developed that reduce or completelyeliminate reliance on internal combustion engines. Electrified vehiclesare one type of vehicle being developed for this purpose. In general,electrified vehicles differ from conventional motor vehicles becausethey are selectively driven by battery powered electric machines.Conventional motor vehicles, by contrast, rely exclusively on theinternal combustion engine to propel the vehicle.

Numerous vehicle assemblies are employed to house components ofelectrified vehicles. One example of such an assembly is the batteryassembly, which houses a plurality of battery cells that are employed topower electric machines and other electric loads of the electrifiedvehicle. It may be desirable to restrict moisture ingress into aninterior of the vehicle assembly.

SUMMARY

A sealing system according to an exemplary aspect of the presentdisclosure includes, among other things, an exterior plate, an interiorplate, a first seal received against the exterior plate and configuredto restrict moisture ingress through the exterior plate and a secondseal received against the interior plate and configured to restrictmoisture ingress through the interior plate.

In a further non-limiting embodiment of the foregoing system, tubing isreceived through the exterior plate and the interior plate.

In a further non-limiting embodiment of either of the foregoing systems,the tubing is received through openings that extend through each of theexterior plate and the interior plate, the first seal and the secondseal both positioned about the tubing.

In a further non-limiting embodiment of any of the foregoing systems,the system includes fasteners that secure the exterior plate relative tothe interior plate.

In a further non-limiting embodiment of any of the foregoing systems,the fasteners are received through peripheral openings formed in boththe exterior plate and the interior plate.

In a further non-limiting embodiment of any of the foregoing systems,the peripheral openings of the exterior plate open into caps, the capshaving internal threads for engaging the fasteners.

In a further non-limiting embodiment of any of the foregoing systems,the first seal is a peripheral seal and the second seal is an O-ringseal.

In a further non-limiting embodiment of any of the foregoing systems,the first seal is a polymer infiltration and pyrolysis (PIP) seal andthe second seal is a rubber seal.

In a further non-limiting embodiment of any of the foregoing systems,the exterior plate includes a recessed surface, and the first seal isreceived within the recessed surface.

In a further non-limiting embodiment of any of the foregoing systems,the interior plate includes a recessed surface, and the second seal isreceived within the recessed surface.

A vehicle assembly according to another exemplary aspect of the presentdisclosure includes, among other things, an enclosure including a wall,a sealing system mounted to the wall and including an exterior platecontiguous with an exterior surface of the wall, an interior platecontiguous with an interior surface of the wall, and a seal disposedbetween the exterior plate and the interior plate. Tubing extendsthrough the interior plate, the wall and the exterior plate.

In a further non-limiting embodiment of the foregoing assembly, the sealis a peripheral seal.

In a further non-limiting embodiment of either the foregoing assemblies,the seal is an O-ring seal.

In a further non-limiting embodiment of any of the foregoing assemblies,the seal is a peripheral seal and comprising a second seal that is anO-ring seal.

In a further non-limiting embodiment of any of the foregoing assemblies,the seal is disposed about the tubing and is configured to restrictmoisture ingress through an opening of the wall.

A vehicle according to another exemplary aspect of the presentdisclosure includes, among other things, a plurality of battery cells,an enclosure that houses the plurality of battery cells, a cold plate incontact with the plurality of battery cells and a sealing system mountedto a wall of the enclosure and configured to seal around tubing thatextends from the cold plate, through the sealing system and the wall, toan exterior of the enclosure.

In a further non-limiting embodiment of the foregoing vehicle, thetubing extends along a linear axis that excludes any bends.

In a further non-limiting embodiment of either of the foregoingvehicles, the sealing system includes an exterior plate, an interiorplate, O-ring seals, and a peripheral seal.

In a further non-limiting embodiment of any of the foregoing vehicles,the exterior plate is received against an exterior surface of the walland the interior plate is received against an interior surface of thewall.

In a further non-limiting embodiment of any of the foregoing vehicles,the O-ring seals are positioned around the tubing between the interiorplate and the wall and the peripheral seal is positioned around thetubing between the exterior plate and the wall.

The embodiments, examples and alternatives of the preceding paragraphs,the claims, or the following description and drawings, including any oftheir various aspects or respective individual features, may be takenindependently or in any combination. Features described in connectionwith one embodiment are applicable to all embodiments, unless suchfeatures are incompatible.

The various features and advantages of this disclosure will becomeapparent to those skilled in the art from the following detaileddescription. The drawings that accompany the detailed description can bebriefly described as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically illustrates a powertrain of an electrified vehicle.

FIG. 2 is an outside view of a vehicle assembly.

FIG. 3 is an inside view of the vehicle assembly of FIG. 2.

FIG. 4 illustrates a top view of the vehicle assembly of FIG. 2.

FIG. 5 illustrates an exploded view of a sealing system of a vehicleassembly.

FIGS. 6A, 6B and 6C illustrate an exterior plate of the sealing systemof FIG. 5.

FIG. 7 illustrates an interior plate of the sealing system of FIG. 5.

FIG. 8 illustrates a seal of the sealing system of FIG. 5.

FIG. 9 illustrates a battery assembly that employs a plated sealingsystem.

FIG. 10 is a cross-sectional view of the battery assembly of FIG. 9.

DETAILED DESCRIPTION

This disclosure details a plated sealing system for a vehicle assembly.The sealing system may include an exterior plate, an interior plate andone or more seals positioned between the exterior plate and the interiorplate. In some embodiments, the sealing system is part of a vehicleassembly that includes an enclosure having a wall and tubing extendingthrough the interior plate, the wall, and the exterior plate. Thesealing system restricts moisture ingress through the plates and thewall into an interior of the enclosure. In other embodiments, thevehicle assembly is a battery assembly that includes a plurality ofbattery cells and a cold plate in contact with the battery cells. Thesealing system seals the tubing-to-wall interface of the assembly torestrict moisture ingress inside the battery assembly. These and otherfeatures are discussed in greater detail in the following paragraphs ofthis detailed description.

FIG. 1 schematically illustrates a powertrain 10 for an electrifiedvehicle 12. Although depicted as a hybrid electric vehicle (HEV), itshould be understood that the concepts described herein are not limitedto HEV's and could extend to other electrified vehicles, including, butnot limited to, plug-in hybrid electric vehicles (PHEV's) and batteryelectric vehicles (BEV's).

In one embodiment, the powertrain 10 is a power-split powertrain systemthat employs a first drive system and a second drive system. The firstdrive system includes a combination of an engine 14 and a generator 18(i.e., a first electric machine). The second drive system includes atleast a motor 22 (i.e., a second electric machine), the generator 18,and a battery assembly 24. In this example, the second drive system isconsidered an electric drive system of the powertrain 10. The first andsecond drive systems generate torque to drive one or more sets ofvehicle drive wheels 28 of the electrified vehicle 12. Although apower-split configuration is shown, this disclosure extends to anyhybrid or electric vehicle including full hybrids, parallel hybrids,series hybrids, mild hybrids or micro hybrids.

The engine 14, which in one embodiment is an internal combustion engine,and the generator 18 may be connected through a power transfer unit 30,such as a planetary gear set. Of course, other types of power transferunits, including other gear sets and transmissions, may be used toconnect the engine 14 to the generator 18. In one non-limitingembodiment, the power transfer unit 30 is a planetary gear set thatincludes a ring gear 32, a sun gear 34, and a carrier assembly 36.

The generator 18 can be driven by the engine 14 through the powertransfer unit 30 to convert kinetic energy to electrical energy. Thegenerator 18 can alternatively function as a motor to convert electricalenergy into kinetic energy, thereby outputting torque to a shaft 38connected to the power transfer unit 30. Because the generator 18 isoperatively connected to the engine 14, the speed of the engine 14 canbe controlled by the generator 18.

The ring gear 32 of the power transfer unit 30 may be connected to ashaft 40, which is connected to vehicle drive wheels 28 through a secondpower transfer unit 44. The second power transfer unit 44 may include agear set having a plurality of gears 46. Other power transfer units mayalso be suitable. The gears 46 transfer torque from the engine 14 to adifferential 48 to ultimately provide traction to the vehicle drivewheels 28. The differential 48 may include a plurality of gears thatenable the transfer of torque to the vehicle drive wheels 28. In oneembodiment, the second power transfer unit 44 is mechanically coupled toan axle 50 through the differential 48 to distribute torque to thevehicle drive wheels 28.

The motor 22 can also be employed to drive the vehicle drive wheels 28by outputting torque to a shaft 52 that is also connected to the secondpower transfer unit 44. In one embodiment, the motor 22 and thegenerator 18 cooperate as part of a regenerative braking system in whichboth the motor 22 and the generator 18 can be employed as motors tooutput torque. For example, the motor 22 and the generator 18 can eachoutput electrical power to the battery assembly 24.

The battery assembly 24 is an example type of electrified vehiclebattery. The battery assembly 24 may include a high voltage tractionbattery pack that includes a plurality of battery arrays, or groupingsof battery cells, capable of outputting electrical power to operate themotor 22 and the generator 18. Other types of energy storage devicesand/or output devices can also be used to electrically power theelectrified vehicle 12.

In one non-limiting embodiment, the electrified vehicle 12 has two basicoperating modes. The electrified vehicle 12 may operate in an ElectricVehicle (EV) mode where the motor 22 is used (generally withoutassistance from the engine 14) for vehicle propulsion, thereby depletingthe battery assembly 24 state of charge up to its maximum allowabledischarging rate under certain driving patterns/cycles. The EV mode isan example of a charge depleting mode of operation for the electrifiedvehicle 12. During EV mode, the state of charge of the battery assembly24 may increase in some circumstances, for example due to a period ofregenerative braking. The engine 14 is generally OFF under a default EVmode but could be operated as necessary based on a vehicle system stateor as permitted by the operator.

The electrified vehicle 12 may additionally operate in a Hybrid (HEV)mode in which the engine 14 and the motor 22 are both used for vehiclepropulsion. The HEV mode is an example of a charge sustaining mode ofoperation for the electrified vehicle 12. During the HEV mode, theelectrified vehicle 12 may reduce the motor 22 propulsion usage in orderto maintain the state of charge of the battery assembly 24 at a constantor approximately constant level by increasing the engine 14 propulsionusage. The electrified vehicle 12 may be operated in other operatingmodes in addition to the EV and HEV modes within the scope of thisdisclosure.

FIGS. 2, 3 and 4 illustrate portions of a vehicle assembly 54 that canbe incorporated into an electrified vehicle. For example, the vehicleassembly 54 could be employed within the electrified vehicle 12 ofFIG. 1. The vehicle assembly 54 could be any assembly that requiressealing to restrict moisture ingress into the vehicle assembly 54. Inone non-limiting embodiment, the vehicle assembly 54 is a high voltagetraction battery assembly for an electrified vehicle (see, for example,the embodiment of FIG. 9).

The vehicle assembly 54 includes an enclosure 60 that defines aninterior 66 for housing one or more vehicle components. The enclosure 60includes a plurality of walls 65 that surround the interior 66. Theenclosure 60 may encompass any size, shape or configuration. That is,the enclosure 60 is not limited to the specific configuration shown inFIGS. 2 and 3. For example, although shown with an open top in FIGS. 2and 3, another wall 65 could extend along the top of the enclosure 60 tocover the vehicle components housed in the interior 66.

Tubing 70 may extend through one of the walls 65 of the enclosure 60.The tubing 70 may extend within openings 72 formed through the wall 65.The tubing 70 may connect between components inside the enclosure 60 andcomponents exterior from the enclosure 60, such as to communicate fluidsbetween the interior 66 and the exterior. The openings 72 are holesformed through the wall 65 and therefore must be sealed to preventmoisture from entering the interior 66 of the enclosure 60. A sealingsystem 74 may therefore be mounted to the wall 65 to seal any leakagepaths created by the openings 72.

In one embodiment, the sealing system 74 includes an exterior plate 76and an interior plate 78. The exterior plate 76 is contiguous with anexterior surface 80 of the wall 65 (see FIG. 2), and the interior plate78 is contiguous with an interior surface 82 of the wall 65 (see FIG.3). A portion of the wall 65 is sandwiched between the exterior plate 76and the interior plate 78. The tubing 70 extends through the interiorplate 78, then through the wall 65, and then through the exterior plate76 to communicate between the interior 66 and the exterior of theenclosure 60 (best illustrated in FIG. 4). As further discussed below,the sealing system 74 may include numerous mechanisms for sealing anyleakage paths that exist through the wall 65.

FIG. 5, with continued reference to FIGS. 2, 3 and 4, furtherillustrates the sealing system 74. The sealing system 74 may include theexterior plate 76, the interior plate 78, fasteners 84 (two shown),O-ring seals 86 (two shown) and a peripheral seal 88. As stated above,the exterior plate 76 is configured for attachment to an exteriorsurface 80 of the wall 65 and the interior plate 78 is configured forattachment to an interior surface 82 of the wall 65. In one non-limitingembodiment, the exterior plate 76 and the interior plate 78 are cast,aluminum plates and may take any size or shape.

The fasteners 84 secure the interior plate 78 relative to the exteriorplate 76. For example, the fasteners 84 may be tightened to secure theexterior plate 76 and the interior plate 78 together on opposing sidesof the wall 65 (see FIG. 4). In one embodiment, the fasteners 84 may bereceived in a direction from the interior surface 82 toward the exteriorsurface 80 of the wall 65. The fasteners 84 are received throughperipheral openings 90 of the interior plate 78 and peripheral openings92 of the exterior plate 76. In one non-limiting embodiment, thefasteners 84 are bolts, although other types of fasteners are alsocontemplated. The sealing system 74 may utilize any amount of fasteners84 to secure the interior plate 78 relative to the exterior plate 76.

In one embodiment, the O-ring seals 86 are rubber seals. One suitablerubber material includes ethylene propylene diene monomer. However,other materials are also contemplated. The sealing system 74 may utilizeany amount of O-ring seals 86 and not necessarily just the two that areshown in FIG. 5. The peripheral seal 88 may be a polymer infiltrationand pyrolysis (PIP) seal that is fabricated using ceramic matrixcomposites that include a low viscosity polymer infiltrated into aceramic structure. The O-ring seals 86 are received over the tubing 70(e.g., one seal per tube) and abut against the interior plate 78 (i.e.,the O-ring seals 86 are positioned on a first side of wall 65), whereasthe peripheral seal 88 is received against the exterior plate 76 (i.e.,the peripheral seal 88 is positioned on a second, opposite side of thewall 65 from the O-ring seals 86, as shown in FIG. 4). In anotherembodiment, the O-ring seals 86 could be replaced by a one-piece rubberseal or another PIP seal.

The tubing 70 is sized to extend through openings 94 of the interiorplate 78 and openings 96 of the exterior plate 76. In one non-limitingembodiment, the tubing 70 may be fixedly secured to the exterior plate76 and the interior plate 78. Suitable attachment methodologies include,but are not limited to, brazing, welding, gluing and soldering.

FIGS. 6A, 6B and 6C illustrate additional features of the exterior plate76. The exterior plate 76 includes a first face 77 and an opposingsecond face 79. Once installed, the first face 77 of the exterior plate76 abuts the exterior surface 80 of the wall 65 and the second face 79faces away from the wall 65 (see FIG. 4).

The first face 77 may include a recessed surface 81. The recessedsurface 81 is sized and shaped to receive the peripheral seal 88. In oneembodiment, the shape of the recessed surface 81 matches the shape ofthe peripheral seal 88. As best shown in FIG. 6B, the peripheral seal 88protrudes slightly outwardly from the recessed surface 81 such that aportion of the peripheral seal 88 extends above the first face 77. Theperipheral seal 88 seals around a periphery of the exterior plate 76,including around both the peripheral openings 92 and the openings 96.

The peripheral openings 92 and the openings 96 extend through theexterior plate 76. In one embodiment, the peripheral openings 92 and theopenings 96 extend through the first face 77 and the second face 79. Theperipheral openings 92 open into caps 83 that protrude from the secondface 79. In one embodiment, the caps 83 are closed-ended and includeinternal threading for engaging the fasteners 84 (see FIG. 5) of thesealing system 74.

FIG. 7 further illustrates the peripheral seal 88 of the sealing system74 of FIG. 5. The peripheral seal 88 includes a plurality of rings 85and arms 87 that connect between adjacent rings 85. The rings 85 sealaround the peripheral openings 92 and the openings 96 of the exteriorplate 76, which is shown in FIGS. 6A, 6B and 6C, to restrict moistureingress. That is, the rings 85 of the peripheral seal 88 seal anyleakage path that may exist through the peripheral openings 92 and theopenings 96.

FIG. 8 further illustrates the interior plate 78 of the sealing system74 of FIG. 5. The interior plate 78 includes a first face 91 and anopposing second face 93. Once installed, the first face 91 of theinterior plate 78 abuts the interior surface 82 of the wall 65, whereasthe second face 93 faces toward the interior 66 of the enclosure 60 (seeFIG. 4). The first face 91 may include a recessed surface 95. Therecessed surface 95 is sized and shaped to receive one or more O-ringseals 86. The O-ring seals 86 seal around the openings 94 which receivethe tubing 70. Both the peripheral openings 90 and the openings 94extend through the interior plate 78 (i.e., extend through the firstface 91 and the second face 93).

FIGS. 9 and 10 illustrate a battery assembly 154 for use in anelectrified vehicle. The battery assembly 154 is one non-limitingexample of a vehicle assembly that may benefit from the teachings ofthis disclosure. The exemplary battery assembly 154 includes batteryarrays 156, which can be described as groupings of battery cells 158,for supplying electrical power to various vehicle components. Althoughtwo battery arrays 156 are illustrated in FIG. 9, the battery assembly154 could include a single battery array or multiple battery arrayswithin the scope of this disclosure. In other words, this disclosure isnot limited to the specific configuration shown in FIG. 9.

Each battery array 156 includes a plurality of battery cells 158 thatmay be stacked side-by-side along a span length of each battery array156. Although not shown in the highly schematic depictions of FIGS.9-10, the battery cells 158 may be electrically connected to one anotherusing busbar assemblies. In one embodiment, the battery cells 158 areprismatic, lithium-ion cells. However, battery cells having othergeometries (cylindrical, pouch, etc.) and/or other chemistries(nickel-metal hydride, lead-acid, etc.) could alternatively be utilizedwithin the scope of the disclosure.

An enclosure 160 (shown in phantom in FIG. 9) surrounds the batteryarrays 156). The enclosure 160 defines an interior 166 for housing thebattery arrays 156 and, potentially, other components of the batteryassembly 154. In one non-limiting embodiment, the enclosure 160 includesa tray 162 and a cover 164 which establish a plurality of walls 165 thatsurround the interior 166.

During some conditions, heat may be generated by the battery cells 158of the battery arrays 156 during charging and discharging operations.Heat may also be transferred into the battery cells 158 during vehiclekey-off conditions as a result of relatively hot ambient conditions.During other conditions, such as relatively cold ambient conditions, thebattery cells 158 may need heated. A cold plate 199 may therefore beutilized as part of a thermal management system for thermallyconditioning (i.e., heating or cooling) the battery cells 158.

In one non-limiting embodiment, the battery arrays 156 of the batteryassembly 154 are positioned atop the cold plate 199 so that the coldplate 199 is in contact with the bottom surface of each battery cell158. A fluid may be circulated through the cold plate 199 to either addor remove heat to/from the battery assembly 154. Tubing 170 provides aconduit for communicating the fluid into and out of the cold plate 199.In one embodiment, the tubing 170 protrudes through one of the walls 165of the enclosure 160 for connection to other thermal managementcomponents.

In one non-limiting embodiment, the tubing 170 extends laterally awayfrom an edge of the cold plate 199 and extends along a completely linearaxis (i.e., excludes any bends). The tubing 170 extends through one ofthe walls 165, which in this example is a side wall of the enclosure160. The battery assembly 154 may include a sealing system 174 thatseals around the tubing 170 at locations where the tubing 170 protrudesthrough the wall 165.

Referring now primarily to FIG. 10, the sealing system 174 may includean exterior plate 176, an interior plate 178, a first seal 186 and asecond seal 188. The exterior plate 176 is secured at an exteriorsurface 180 of the wall 165 and the interior plate 178 is secured at aninterior surface 182 of the wall 165. Both the first seal 186 and thesecond seal 188 may be positioned between the exterior plate 176 and theinterior plate 178. In one embodiment, the first seal 186 is positionedaround the tubing 170 and is positioned axially between the interiorsurface 182 of the wall 165 and the interior plate 178 and the secondseal 188 is positioned axially between the exterior surface 180 of thewall 165 and the exterior plate 176.

Although the different non-limiting embodiments are illustrated ashaving specific components or steps, the embodiments of this disclosureare not limited to those particular combinations. It is possible to usesome of the components or features from any of the non-limitingembodiments in combination with features or components from any of theother non-limiting embodiments.

It should be understood that like reference numerals identifycorresponding or similar elements throughout the several drawings. Itshould be understood that although a particular component arrangement isdisclosed and illustrated in these exemplary embodiments, otherarrangements could also benefit from the teachings of this disclosure.

The foregoing description shall be interpreted as illustrative and notin any limiting sense. A worker of ordinary skill in the art wouldunderstand that certain modifications could come within the scope ofthis disclosure. For these reasons, the following claims should bestudied to determine the true scope and content of this disclosure.

What is claimed is:
 1. A vehicle, comprising: a plurality of batterycells; an enclosure that houses said plurality of battery cells; aliquid cooled cold plate housed inside the enclosure and positioned incontact with said plurality of battery cells; and a sealing systemmounted to a wall of said enclosure and configured to seal around tubingthat extends from said cold plate, through each of said sealing systemand said wall, and to an exterior of said enclosure.
 2. The vehicle asrecited in claim 1, wherein said tubing extends along a linear axis thatexcludes any bends.
 3. A vehicle, comprising: a plurality of batterycells; an enclosure that houses said plurality of battery cells; a coldplate in contact with said plurality of battery cells; and a sealingsystem mounted to a wall of said enclosure and configured to seal aroundtubing that extends from said cold plate, through each of said sealingsystem and said wall, and to an exterior of said enclosure, wherein saidsealing system includes an exterior plate, an interior plate, O-ringseals, and a peripheral seal.
 4. The vehicle as recited in claim 3,wherein said exterior plate is received against an exterior surface ofsaid wall and said interior plate is received against an interiorsurface of said wall.
 5. The vehicle as recited in claim 4, wherein saidO-ring seals are positioned around said tubing between said interiorplate and said wall and said peripheral seal is positioned around saidtubing between said exterior plate and said wall.
 6. The vehicle asrecited in claim 3, comprising a fastener received through an opening insaid exterior plate, said interior plate, and said peripheral seal. 7.The vehicle as recited in claim 3, wherein said peripheral seal is apolymer infiltration and pyrolysis (PIP) seal and said O-ring seals arerubber seals.
 8. The vehicle as recited in claim 3, wherein saidperipheral seal includes a plurality of rings and arms that connectbetween adjacent rings of said plurality of arms.
 9. The vehicle asrecited in claim 3, wherein said exterior plate includes peripheralopenings that open into caps.
 10. The vehicle as recited in claim 9,wherein said caps include internal threads configured to engage afastener received through said peripheral openings.
 11. A vehicle,comprising: a battery enclosure; a sealing system including: an exteriorplate received against an exterior wall of said battery enclosure; afirst seal between said exterior wall and said exterior plate; aninterior plate received against an interior wall of said batteryenclosure; a second seal between said interior wall and said interiorplate; and a tube extending through said exterior plate, said firstseal, said interior plate, and said second seal.
 12. The vehicle asrecited in claim 11, wherein said first seal is a polymer infiltrationand pyrolysis (PIP) seal and said second seal is a rubber seal.
 13. Thevehicle as recited in claim 11, comprising a fastener received throughsaid interior plate, said interior wall, said exterior wall, and saidexterior plate.
 14. The vehicle as recited in claim 11, wherein saidfirst seal includes a first ring, a second ring, and an arm connectingbetween said first ring and said second ring.
 15. The vehicle as recitedin claim 11, wherein said first seal is received within a recessedsurface of said exterior plate.